Can't figure out why I can only access my HUB remotely via the mobile app & not laptop

I can't figure this out.

I am trying to manage a hub that is located at a vacation property several states away. Due to the distance and lack of IT knowledge from my property manager, my cable modem/router is rented from the cable company who can provide onsite support if needed ( having any additional equipment, computer or a second router for a VPN at the vacation home is not an option).

I am paying for Remote Admin on my account. When using the mobile android app in my home state, I can connect to the hub remotely. However, I can't connect to the hub remotely using my laptop. When I log in, I get the message that there is no hub registered to the account.

I was at the house last week and I had no issue connecting to the HUB when my laptop was on the same internal network as the HUB. It discovered it easily. I am using the same username and password for both my mobile app and account.

I know I am missing something but I can't figure it out. Is there something in the Mobile App which I can do to allow hub access via my laptop?